File Uploader for WooCommerce < 1.0.4 - Unauthenticated Arbitrary File Upload via add-image-data

Description

The File Uploader for WooCommerce plugin for WordPress is vulnerable to arbitrary file uploads due to missing file type validation in the callback function for the 'add-image-data' REST API endpoint in all versions up to, and including, 1.0.3. This makes it possible for unauthenticated attackers to upload arbitrary files to the Uploadcare service and subsequently download them on the affected site's server which may make remote code execution possible.